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Where will we get ALL that electricity whan most cars are electric?
- Thread starter Rownolds
- Start date
What evidence do you provide for this statistic? I highly doubt its validity.I am already powering my car with fusion generated electricity as are 60% of other Tesla owners. Driving on Sunshine
In our case that fusion reactor is at a very safe 93 million miles away
dhrivnak
Active Member
Or if you are questioning the 60% driving on solar look at the link I provided to see MANY examples.
REALLY?? A survey in which a grand total of 135 people participated is sufficient proof that 60% of ALL Tesla owners are driving on solar??? Is THAT the link to which you are referring?
There's a difference between "does the grid have enough capacity to generate and deliver all the electricity EVs will need" and "where will the energy come from?" There's no doubt we have enough generating capacity for EVs, if we could control timing of charging to some degree. But we still need energy behind the generators, be it natural gas or coal. Or we need more renewables and some combination of storage and timed charging.
dhrivnak
Active Member
give us a better source. Inside EV's had a story saying 30% of all EV owners have solar.
Give you a "better source"? I am not the one making the claim, but without a "better source" I am not going to grab a statistic off a 135 vote panel and apply it to all Tesla owners! It's this kind of statistical analysis (or lack thereof) that gives solar energy proponents a bad name.
Sorry, I guess you didn't.
So let me rephrase...
He has a survey with a very small sample size. You have zero data.
Given the choice, I'll go a little data over none.
I also doubt 60% of all owners have solar. From the owners i know I would guess closer to 60% have or are planning to get solar.
However, my sampling is even smaller.
The other survey mentioned, 30%, is probably a bit low as MS owners tend to have more discretionary funds.
So for the evidence we have, although it is small, the truth is probably between 30% and 60%.
You are correct. I have zero data. It's kinda why I was asking for his source. I am searching for data. Math NOT being my strong-point but let's just take a look. 134 respondents out of >30,000 Tesla owners means a significantly lower than 1% survey pool. To me that is way less than a "little data". It is actually minuscule data--statistically insignificant. It would be the same if someone said only 83 of 30,000 Tesla owners have installed solar (based on the "statistical" data provided in the survey). You'd have to have a +/-99% margin of error. Even your estimate of a statistic -- somewhere between 30-60% -- assumes that those with discretionary funds would opt for solar energy panels on their homes. Personally (since we are just guessing anyway!!) I would be amazed if even 15% of all Tesla owners also had solar arrays.
My point is simply this: If we are going to post a statistic let's try to make sure it is a valid statistic.
While 0.44% poll is indeed statistically insignificant, you have to consider "standard practice" also, e.g. the TV show viewing ratings are based on 2000 set-top boxes distributed to random cable subscribers to measure the interest of over 200 million viewers -- that is a 0.001% poll being used every day to decide the fate of multi-million dollar shows (what gets cancelled / what gets renewed).
OK. So based on this would you also assume that 60% of all Tesla owners world-wide have solar power installed?
Even if this is true (I think there will need to be some upgrades to distribution systems), it doesn't answer where we'll get the energy. Sure, our fleet of fossil-fired assets has more than enough surplus capacity, but if we use that capacity, we need to burn more gas, coal, or oil. The OP's point was to suggest a way to get that energy without more fossil fuels.
My take is this: it sure would be nice if fusion worked out, and I hope that researchers make strides in this direction. Policymakers would be foolish, however, to rely on fusion to solve the pressing need to decarbonize our energy supply. We can't wait for promising new technologies.
If the US had a carbon tax, it would be far easier for all zero-carbon energy companies (including fusion) to get funding.
130 is a decent sample size, the issue is that it isn't a random sample. People who are interested in technology and especially sustainable energy are more likely to see and respond to an online poll, especially if they have solar. If you have solar power installed, and you see a question "Do you have solar installed?", you are significantly more likely to drop in and answer than if you didn't have solar.
Anyway, by my calculations, if you assume 4.5 kWh to refine a gallon of fuel (which is one of the more optimistic figures I've seen, some go as high as 12 kWh), and .35 kWh per mile for the model S (conservative driving can drop it well below .3 kWh, while more spirited driving can push it closer to .4 kWh), a model S can drive 12.85 miles on the electricity needed to refine a single gallon of gasoline.
That means a model S has less environmental impact per mile of driving than a 12 mpg vehicle before the fuel is even burned.
Anyway, by my calculations, if you assume 4.5 kWh to refine a gallon of fuel (which is one of the more optimistic figures I've seen, some go as high as 12 kWh), and .35 kWh per mile for the model S (conservative driving can drop it well below .3 kWh, while more spirited driving can push it closer to .4 kWh), a model S can drive 12.85 miles on the electricity needed to refine a single gallon of gasoline.
That means a model S has less environmental impact per mile of driving than a 12 mpg vehicle before the fuel is even burned.
Well, I think more BEVs would imply cheaper batteries, which would help increase grid efficiency and renewable utilization. And of course, if renewables force a change in pricing of electricity distribution it'll only help BEVs. Then there'd be the effect of filling in the nighttime bathtub and higher grid utilization which could help the grid investment economics in a way that would accelerate efficiency improvements.
I think there's plenty of positive feedback to be expected.
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I agree that 130 would be an adequate sample size to pin the probability down to within +/- .1 assuming a random sample, but I also agree that the sample is likely to be somewhat biased (not random) for the reason you give. I personally would be surprised if even 20% of drivers had solar, but that is definitely just a WAG (new acronym for me) on my part.
Do you have a source for the claim that 4.5 kwh of electricity is used to refine a gallon of gas? I am having trouble finding a reliable source for this. (Some numbers I saw seemed to show that 10% of the energy content of oil is lost in refining, but only 15% of this energy, around .5 kwhs, comes from electricity, but I'm not sure about that claim either.)
(For the model S calculation, I would add an extra 20% energy use for charging and Vampire losses.)
Finally, I agree with Robert - the key question is not the adequacy of the grid but the source of the energy.
4.5 kWh of electricity to refine a gallon of gasoline is not correct. On average it's less than 0.2 kWh of electricity per gallon. A little over 95% of the 5-6 kWh of energy used to refine a gallon of gasoline is thermal energy produced from burning petroleum byproducts made in the refinery (mostly) and burning natural gas (to a somewhat lesser extent). Less than 5% of the energy used in oil refineries is electricity. There's a discussion on this subject on TMC starting here
Also, it's common for oil refineries to have Cogen plants to make their own electricity.
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